The magnetic field effect on the current-voltage characteristic curves of glow discharge in argon at low pressures has been experimentally investigated. The electrical discharge was ignited in a stainless steel tapered chamber of a nominal volume of 0.5m3 immersed inside a water-cooled coil capable of delivering a magnetic field of strength B of up to 0.42T. Three water-cooled electrodes were inserted into the chamber up to a point where their tips were 20cm away from the surface of the central column of the chamber. An enhancement of the electric field configuration within the region of the electrode assembly was performed by threading one of the electrodes with stainless circular discs(80mm and 140mm in diameter) in various forms(attached or separated). Depending upon the experimentally operating conditions, different glow discharge voltages and their corresponding currents were recorded with an optimum current of 10A at B= 500G and P= 10-3 mbar. A discharge current of 11.7A was reached as the gas pressure was raised by an order of magnitude at B=10G at d=20cm with very slight changes in the discharge voltage. Experimental results were found to be sensitive to the geometry of the electrode assembly, P, and B. Elevation of cathode surface temperature was recorded and found effective in reducing the pumping down cycle over a process of glow discharge cleaning of the internal chamber surface.
A series of new 4-(((4-(5-(Aryl)-1,3,4-oxadiazol-2-yl)benzyl)oxy)methyl)-2,6-dimethoxy phenol (6a-i) were synthesized from cyclization of 4-(((4-hydroxy-3,5-dimethoxy benzyl)oxy)methyl)benzohydrazide with substituted carboxylic acid in the presences of phosphorusoxy chloride.The resulting compounds were characterized by IR, 1H-NMR, 13C-NMR, and HRMS data. 2,2-Diphenyl-1-picrylhydrazide (DPPH) and ferric reducing antioxidant power (FRAP) assays were used to screen their antioxidant properties. Compounds 6i and 6h exhibited significant antioxidant ability in both assay. Furthermore, type of substituent and their position of the aryl attached 1,3,4-oxadiazole ring at position five are play an important roles in enhancing or declining the antio
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Software-defined networks (SDN) have a centralized control architecture that makes them a tempting target for cyber attackers. One of the major threats is distributed denial of service (DDoS) attacks. It aims to exhaust network resources to make its services unavailable to legitimate users. DDoS attack detection based on machine learning algorithms is considered one of the most used techniques in SDN security. In this paper, four machine learning techniques (Random Forest, K-nearest neighbors, Naive Bayes, and Logistic Regression) have been tested to detect DDoS attacks. Also, a mitigation technique has been used to eliminate the attack effect on SDN. RF and KNN were selected because of their high accuracy results. Three types of ne
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Synthesis and preliminary biological evaluation of imidazo (2, 1-b) Thiazole derivatives is reported. Under Mannich conditions, a series of new imidazo (2, 1-b) Thiazole derivatives were synthesized. Starting from the reaction of 2- amino thiazole with 4- bromo phenyl bromide to produce 5-(4-bromo phenyl) imidazo (2, 1-b) thiazoles, following by introduce the substituted aminomethyl at position 6-by reacting with different aromatic amines under Mannich conditions to afford 6-secondary amine-5-(4-bromo phenyl) imidazo (2,1-b) thiazole in high yields.
FT-IR, 1H NMR, and 13C NMR techniques were used to characterize the synthesized derivatives. In addition, all compounds were tested for their antioxidant activity, and thr
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This work discusses the beginning of fractional calculus and how the Sumudu and Elzaki transforms are applied to fractional derivatives. This approach combines a double Sumudu-Elzaki transform strategy to discover analytic solutions to space-time fractional partial differential equations in Mittag-Leffler functions subject to initial and boundary conditions. Where this method gets closer and closer to the correct answer, and the technique's efficacy is demonstrated using numerical examples performed with Matlab R2015a.
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This study included partial purification of the lipase enzyme from the karnel of the pecan nut. After applying ion exchange chromatography technique using CM-Cellulose, two lipase isoenzymes were observed with specific activity values of 2.66 and 1.7 units/mg protein. The highest activity of both isoenzymes appeared at the optimum pH values of 8 and 6 and at temperatures of 40 and 50 °C, respectively. A pure single band was obtained by using electrophoresis technique and it was found that the approximate molecular weight was 42 kDa for the two isoenzymes. The study dealt with the preparation of the diester compound 1,4-diacetoxybenzene, which was diagnosed by GC-MS and 1H NMR spectrometry. When studying the inhibitio
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A series of 4-(methylsulfonyl)aniline derivatives were synthesized in order to obtain new compounds as a potential anti-inflammatory agents with expected selectivity against COX-2 enzyme. In vivo acute anti-inflammatory activity of the final compounds 11–14 was evaluated in rat using an egg-white induced edema model of inflammation in a dose equivalent to 3 mg/Kg of diclofenac sodium. All tested compounds produced significant reduction of paw edema with respect to the effect of propylene glycol 50% v/v (control group). Moreover, the activity of compounds 11 and 14 was significantly higher than that of diclofenac sodium (at 3 mg/Kg) in the 120–300 minute time interval, while compound 12 expressed a comparable effect to that of di
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This experiment presented essential oils by GC/MS, pigment content, and their antioxidant activities as well as sensory evaluation of delight samples. Limonene (66.88%) was the most prevalent yield. The peels of clementine had DPPH and ABT Scavenging activity. All levels of pigment extract had better scores for all sensory values and recorded acceptable scores in terms of appearance, color, aroma, and overall acceptability compared to control delight. Besides, delight samples containing 15 mg astaxanthin pigment extract showed maximum sensory scores compared to other samples and control delight. On the other hand, the product was less acceptable to the panelists compared to control in the case of the addition of 3.75 mg astaxanthin pigme
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